1. Field of the Invention
The present invention relates to an efficient hardware implementation of the Secure Hash Algorithm (SHA-1) and Message Digest Algorithm (MD5).
2. Description of the Related Art
Hash algorithms and message digests are frequently used in applications such as digital signatures, where it is desirable to verify the authenticity of a document or file. Techniques for producing message digests are beneficial as they reduce the amount of data processing needed to a manageable and consistent level.
The Secure Hash algorithm (SHA-1) is specified in Secure Hash Standard (FIPS PUB 180-1) and is an algorithm that operates on an input data file to produce a condensed representation of that file. Specifically, a message of arbitrary length is processed to produce a message digest consisting of exactly 160 bits.
The Message Digest Algorithm (MD5), developed by Professor Ronald Rivest, has a similar function. It accepts inputs of arbitrary length and produces an output message digest consisting of exactly 128 bits.
Both algorithms may be used as a constituent part of a digital signature application. Both algorithms are computationally intensive and, when implemented in software, as is the norm in prior systems, can take a great number of processor clock cycles to complete.